(i) Field of the Invention
This invention relates to muscle fatigue measuring equipment for estimating the fatigue status of a muscle.
(ii) Description of the Related Art
It is important for athletes, rehabilitants and others to know the fatigue statues of their muscles so as to build their muscular strengths. For information, the relationship between muscle fatigue and passage of time is represented by a graph shown in FIG. 8, for example. During training, muscle fatigue accumulates and increases (muscular strength lowers) as time elapses, as can be seen in an accumulation period. This occurs due to a breakage of a muscle caused by use of the muscle. Then, after the training, the muscle fatigue lowers (muscular strength recovers) as time elapses, as can be seen in a normal recovery period. This occurs due to physiological restoration of the muscle. Then, as can be seen in a super recovery period, the muscle fatigue continuously lowers as time elapses, and after it becomes slightly lower than pre-training muscle fatigue (muscular strength improves), it restores to the pre-training muscle fatigue. This occurs since the muscular strength improves once by a defense mechanism for adapting to a load given during the training but restores to original muscular strength for adapting to life strength.
Based on the relationship between muscle fatigue and passage of time as shown in FIG. 8, trainees (athletes, rehabilitants and others) have relied on subjective estimations to know what their current muscle fatigue statuses are, i.e., whether their muscle fatigues are in accumulation, in recovery or other statuses.
In other words, trainees (athletes, rehabilitants and others) have not been able to know what their current muscle fatigue statuses are, objectively and easily.